Here are PDF's of talks Tim Keller gave at the Urban Plant Life conference in London a couple of years ago. You can also check out the audio/video or grab the podcast. But having documents you can print and search is very helpful. Thanks to @BradAndrews for the heads-up.
1. Gospel Renewal
2. Church & Culture
3. Contextual & Missional
4. Gospel Theology
5. Integrative Ministry
6. Gospel Preaching
7. Gospel Theology
8. Movement Dynamics
9. Church Planting